I think the time is ripe for this kind of software: I'm also working on something very similar. I've put a lot more work into the editing/layout features than the portion for generating the AST—but my scheme for doing it is nearly identical to what you have in your video. A demo video of my editor is here: http://symbolflux.com/projects/tiledtext
When I was working on it before my approach was to use grammatical knowledge of traditional, text-based languages to generate a selection of grammatically valid constructs for your current 'cursor' position; only in the last few weeks did I hit on the idea to do it 'syntax-free' (in my terminology).
My thinking on why 'syntax-free' is The Way to go: if you look at what someone's trying to do when writing a program, it's really: (1) select language construct (2) select parameters as a 'configuration' of selected construct. Text is one way to specify those things, but a far more effective system addresses the fact that that's all you're doing directly, and allows views to be attached after the fact (even if something that's primarily text ends up being the optimal view!).
In case it's helpful to you for communicating the idea to people, I often described the benefit of this kind of system to people as automatically allowing someone who only knows how to read a language, to also be able to write in it—no more remembering the details of how to express construct X in language Y.
When I was working on it before my approach was to use grammatical knowledge of traditional, text-based languages to generate a selection of grammatically valid constructs for your current 'cursor' position; only in the last few weeks did I hit on the idea to do it 'syntax-free' (in my terminology).
My thinking on why 'syntax-free' is The Way to go: if you look at what someone's trying to do when writing a program, it's really: (1) select language construct (2) select parameters as a 'configuration' of selected construct. Text is one way to specify those things, but a far more effective system addresses the fact that that's all you're doing directly, and allows views to be attached after the fact (even if something that's primarily text ends up being the optimal view!).
In case it's helpful to you for communicating the idea to people, I often described the benefit of this kind of system to people as automatically allowing someone who only knows how to read a language, to also be able to write in it—no more remembering the details of how to express construct X in language Y.